Single and multiple blood bags are currently commercially available for storing whole blood and fractions thereof. Most of these blood bags are made of polyvinylchloride (PVC) plasticized with di-2-ethylhexylphthalate (DEHP, also known as dioctyl phthalate or DOP). Plasticizers such as DOP are an essential component of these and other blood bags. (See U.S. Pat. Nos. 4,451,259; 4,286,597; 4,300,559, 4,301,800; 4,507,387; 4,222,379). The use of a plasticizer in the plastic material was needed in order to make the PVC material sufficiently flexible to be made into bags; it was later found, however, that DOP was also needed to increase the storage life of blood to acceptable levels and somehow interacted with the blood. Containers made of a plastic material without a plasticizer caused blood stored in such containers, under the usual blood storage conditions, to exhibit an undesirably high plasma hemoglobin content, indicating that the rate of red blood cell lysis was high.
Many physicians and other interested parties have expressed concern over inclusion of a plasticizer in blood bags (see, for example, Report to the U.S. Consumer Product Safety Commission by the Chronic Hazard Advisory Panel on di(2-ethylhexyl) phthalate (DEHP). U.S. Consumer Product Safety Commission Directorate for Health Sciences, Washington, September 1985, and Journal of The American Association of Blood Banks, May, 1989, Vol. 29, No. 4, pp 287-297). The plasticizer in blood bags is blood extractable, i.e. extractable from the plastic material into the blood. The extracted plasticizer enters the human body along with the blood during infusion and could be significantly detrimental to the health of the body, particularly if there is an allergic reaction or if the plasticizer is built up over numerous infusions.
Attempts have been made to prepare blood bag materials without the use of a plasticizer. (See U.S. Pat. No. 4,301,800). These attempts were generally unsuccessful and resulted in an unacceptably high level of blood cell lysis when used for blood storage materials. Therefore, it would be desirable to have an acceptable blood bag system which does not require the presence of a plasticizer but yet is compatible with stored blood and its components, i.e., does not result in an undesirably high red blood cell lysis when storing red blood cells. Vitamin E has been shown in some instances to have beneficial effects on blood. (See, for example, S. Luczek and F. Wolf, German Medical Monthly, Vol. VIII, No. 5, Stuttgart, May 1963, pp. 182-185; I. Kurokawa et al., Vitamins (Japan) 39, (2), 1969, pp. 86-90; I. Kurokawa et al., Vitamins (Japan) 40, (3), 1969 pp. 206-209; and I. Kurokawa et al., The Journal of Vitaminology, 16, 1970 pp. 180-189).